A micro impinging jet with supercritical carbon dioxide
| Autor: | Stephen Adeoye, Anatoly Parahovnik, Yoav Peles |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Fluid Flow and Transfer Processes
Mass flux Jet (fluid) Materials science Mechanical Engineering Nozzle Reynolds number 02 engineering and technology Heat transfer coefficient Mechanics 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Supercritical fluid 010305 fluids & plasmas symbols.namesake Heat flux 0103 physical sciences Heat transfer symbols 0210 nano-technology |
| Zdroj: | International Journal of Heat and Mass Transfer. 170:121028 |
| ISSN: | 0017-9310 |
| Popis: | A micro device with a 206 µm nozzle diameter and a standoff of 7.3 was fabricated and used to study the characteristics of micro jet impinging heat transfer with supercritical CO2. The issuing jet impinged on a 500 µm thick fused silica substrate measuring 30.5 × 1.9 mm2, onto which a heater, three temperature sensors (RTDs), and their respective leads were sputtered. The RTDs were arranged in a concentric manner with r/d values of 0.21, 1.44, and 2.89. Four holes were drilled into the device to allow passage of spent fluid, which were collected in a single channel out of the medium. The effects of heat flux, radial positions, mass flux and inlet temperature were studied for a pressure of 7.45 MPa — higher than the supercritical pressure of CO2. The highest local heat transfer coefficient of ~40,000 W/m2K was recorded at the RTD closest to the stagnation region at a heat flux of 54.5 W/cm2 and an inlet Reynolds number of approximately 15,500, corresponding to conditions near the pseudocritical temperature. Deviations between experiments and available correlations were noted especially at higher Reynolds number. A Nusselt number correlation for micro jet impingement with sCO2 was proposed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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